= Michael Nielsen
{c}
{tag=Physicist}
{wiki}
= Michael A. Nielsen
{c}
{synonym}
<Michael Nielsen> proved a precise criterion for converting one pure <quantum state> of a <bipartite quantum system> into another using <LOCC>. If $\lambda_\psi$ and $\lambda_\phi$ are the <eigenvalue> lists of their <reduced density operators>, the deterministic conversion $|\psi\rangle\to|\phi\rangle$ is possible exactly when $\lambda_\psi\prec\lambda_\phi$, a <majorization> condition. Thus the descending partial sums for the initial list must not exceed those for the target list. For example, $(1/2,1/2)\prec(1,0)$ permits converting a <Bell state> into a <product state>; the reverse conversion is forbidden by this criterion.<Conditions for a class of entanglement transformations by Michael A. Nielsen>[Theorem 1, equations (1)–(2)]{ref}
\Image[https://commons.wikimedia.org/wiki/Special:Redirect/file/Michael%20Nielsen%20(cropped).jpg?width=250]
{title=Portrait of <Michael Nielsen>}
{description=Photograph by Mike Peel (www.mikepeel.net). https://creativecommons.org/licenses/by-sa/4.0/[CC BY-SA 4.0], via Wikimedia Commons.}
{source=https://commons.wikimedia.org/wiki/File:Michael_Nielsen_(cropped).jpg}
{width=250}
Back to article page
